The Cracking Elements Method (CEM) is a numerical tool for simulation of quasi-brittle fracture. It neither needs remeshing, nor nodal enrichment, or a complicated crack-tracking strategy. The cracking elements used in the CEM can be considered as a special type of Galerkin finite elements. A disadvantage of the CEM is that it uses nonlinear interpolation of the displacement field (e.g. Q8 and T6 elements

A design optimization framework is proposed for process parameters in additive manufacturing. A finite element approximation of the coupled thermomechanical model is used to simulate the fused deposition of heated material and compute the objective function for each analysis. Both gradient-based and gradient-free optimization methods are developed. The gradient-based approach, which results in a balance

The present paper introduces a methodology for formulating two-dimensional structural theories featuring arbitrary kinematic fields. In the proposed approach, each displacement variable can be examined through an independent expansion function, enabling the integration of both classical and higher-order theories within a unified framework. The Carrera Unified Formulation is used to derive the governing

In this paper, a three-dimensional arbitrary Lagrangian-Eulerian (ALE) formulation based on the consistent corotational method for flexible structures' large deformation problems is proposed. In contrast with the Lagrangian formulations, the proposed formulation can accurately describe moving boundary and load problems using moving nodes. The ALE formulation for flexible structures with an arbitrarily

In this paper, an approach to model thin composite plates reinforced with curvilinear fibres is presented and applied to analyse modes of vibration. Particular attention is given to plates with non-standard geometries, which are less commonly addressed in studies on this topic. Aiming to achieve accuracy with a small number of degrees-of-freedom, the model is based on Kirchhoff’s plate theory, combined

For additive manufacturing of fiber-reinforced composites, integrated structural topology optimization and deposition path planning is critical in capturing the anisotropic material feature for designing dynamic performance-oriented structures. Hence, this paper proposes a concurrent optimization method for simultaneously optimizing the structural topology and the fiber deposition path. The Solid Orthotropic

This paper presents a computationally effective approach for crack propagation under mechanical and thermal loads based on an adaptive mesh refinement (AMR) approach tailored for our recently developed enhanced local damage model. The mesh-dependent issue encountered in the classical local theories is effectively mitigated by incorporation of fracture energy and element characteristic length into the

Fracture in quasi-brittle materials, such as refractories and reinforced concrete, involves complex mechanisms due to a progressive micro-cracking process within a fracture process zone (FPZ). This study employs Wu's phase field model (PFM) to simulate fracture behaviour in a magnesia spinel refractory. The PFM integrates fracture mechanics and damage mechanics, predicting tortuous crack patterns when

At the mesoscale, concrete is considered a three-phase composite material comprising stone, mortar, and the interfacial transition zone. Even though mortar is an important component of concrete, its material parameters have not been determined systematically, and they are often modeled by assuming that they are weaker versions of the concrete parameters. Therefore, accurately describing the role of

The mechanical behaviour of textile materials, fundamental to textile composites, is critical for designing advanced material solutions. Mechanical modelling of textiles is highly complex due to the interactions between yarns, resulting in distinct nonlinear characteristics for different textile patterns. Therefore, engineering methods are essential for analysing loading scenarios and integrating decisions

Effective data reduction techniques are crucial for enhancing computational efficiency in complex industrial processes such as forging. In this study, we investigate various discretization and mesh adaptivity strategies using Proper Orthogonal Decomposition (POD) to optimize data reduction fidelity in forging simulations. We focus particularly on r-adaptivity techniques, which ensure a consistent number

This paper investigates the influence of surface roughness on multiple necking formation in additive manufactured porous ductile plates subjected to dynamic plane strain stretching. For this purpose, we have developed a computational model in ABAQUS/Explicit which includes surface texture and discrete voids measured from 3D-printed metallic specimens using optical profilometry and X-ray tomography

This study investigates the buckling behavior of cylindrical shells composed of Functionally Graded Materials (FGMs) when subjected to axial compression, challenging conventional assumptions regarding the influence of Poisson’s effect in homogeneous materials. To address this, we utilize a numerical approach employing the Asymptotic Numerical Method (ANM). Contrary to the expected linear pre-buckling

Failure mechanism of 3D structures cannot always be produced by the low-order finite elements due to the so-called volumetric locking effect. In this paper, dual numerical approaches based on the bubble face-based smoothed finite element method (bFS-FEM) are developed, ensuring that the locking problem is prevented and accurate load factors of elastic-perfectly plastic structures under cyclic actions

Elastic-Plastic-Damage material models are widely adopted for the numerical modelling of concrete because of their capability of representing pressure sensitive 3D material behaviour considering permanent inelastic deformations as well as degradation of material moduli beyond the elastic range. In this paper, we develop a non-associative multi-surface plastic-damage material model for the 3D solid

This paper explores mesoscale conduction-based modeling of Laser Directed Energy Deposition (LDED) for metallic materials. We benchmark the forward Euler (explicit) time integration strategy against the backward Euler (implicit) scheme using two experimentally validated simulations. Our results demonstrate the explicit scheme’s faster computational speed. Additionally, we identify previously overlooked

In this study, we propose a multiscale thickness optimization method for designing micro-shell structure assuming that the macrostructure consists of multiple micro-shell structures. The micro-shell structures are connected to the macrostructure using the NIAH (Novel numerical implementation of asymptotic homogenization) method. The distributed thickness of the micro-shell structures is used as design

In this article, a strategy for efficient computational cost reduction of numerical simulations for complex industrial applications is developed and evaluated on multiphysics problems. The approach is based on the adaptive stopping criterion for iterative linear solvers previously implemented for elliptic partial differential equations and the convection–diffusion equation. Control of the convergence

This study presents a multi-objective topology optimization method tailored to structures fabricated from functionally graded materials (FGMs), coated FGMs, and coated fiber-reinforced composite materials (FRCMs) with fixed fiber thickness. The design objective is the simultaneous minimization of elastic and thermal compliance. The material properties of these composite materials were derived to generate

Finite-element analysis is the only means to determine the load distribution of large slewing bearings considering flexible bearing rings and supporting structures. For reliable results, the plausibility of the models need to be validated. Previous attempts on validating a finite-element model of a slewing bearing against measurement results have indicated a huge dependence of the deformation on tolerances

This paper presents a numerical and experimental assessment of the static behaviour of thick sandwich beams using the mixed {3,2}-Refined Zigzag Theory (RZT{3,2}(m)). The displacement field of the RZT{3,2}(m) assumes a piecewise continuous cubic zigzag distribution for the axial contribution and a smoothed parabolic variation for the transverse one. At the same time, the out-of-plane stresses are assumed

In this paper we address one of the major difficulties which is the nonconvex behavior of the domains while finding the solution of the problems. The part of the domain where the nonsmoothness appears is where the challenge arises and the way that area is handled using different numerical methods reveals the effectiveness of these techniques. Here in this article, we study the semilinear parabolic

This paper proposes an original method to determine the gear tooth root stresses from a 3D finite element (FE) flexible multibody approach and a full-FE contact-based formulation. The contact problem is dealt with an augmented Lagrangian formulation whereas the analysis is performed by a preconditioned gradient solver (PCG). Tooth flank modifications are directly introduced within the 3D model. This

This paper investigates the application of immersed methods to simplify the discretisation and modelling process for meso-scale geometries in fibre-reinforced composites. The geometry of meso-scale structures in fibre-reinforced composites can often be categorised as complex, and frequently presents considerable challenges for meshing software. This complexity necessitates either time-consuming manual

The “poker chip problem” was originally investigated experimentally to create hydrostatic tension in rubber-like materials. Different modes of contact failure were already described during these experiments. Since then, this problem has proven to be useful for investigating the detachment mechanisms of dry adhesives. This is primarily achieved with FE simulations, as many important quantities cannot

Manufacturing processes of composites involve a margin of parameter variability (e.g., geometric, mechanical, loading) which results in an inaccurate prediction of their dynamics when considered with exact assumptions. Real-time calculation of such structures confronts engineers with several challenges (e.g., dimension of finite element model, size of parameter space, uncertainty level, nonlinearity)

A two-level version for a recent semi-hybrid-mixed finite element approach for modeling Stokes and Brinkman flows is proposed. In the context of a domain decomposition of the flow region Ω, composite divergence-compatible finite elements pairs in H(div,Ω)×L2(Ω) are utilized for discretizing velocity and pressure fields, using the same approach previously adopted for two-level mixed Darcy and stress

This work comprehensively investigates key parameters associated with a recently proposed non-intrusive coupling strategy for multiscale structural problems. The IGL-GFEMgl combines the Iterative Global Local Method and the Generalized Finite Element Method with global–local enrichment, GFEMgl. Different scales of the problem are solved using distinct finite element codes: the commercial software Abaqus

Several methods have been developed to model the dynamic behavior of saturated porous media. However, most of them are suitable only for small strain and small displacement problems and are built in a monolithic way, so that individual improvements in the solution of the solid or fluid phases can be difficult. This study shows a macroscopic approach through a partitioned fluid–solid coupling, in which

Deep energy method (DEM) has shown its successes to solve several problems in solid mechanics recently. It is known that determining proper integration scheme to precisely calculate total potential energy (TPE) value is crucial to achieve high-quality training performance of DEM but it has not been discovered satisfactorily in previous related works. To shed light on this matter, this study focuses

This paper presents a Chimera approach for the thermal problems in welding and metallic Additive Manufacturing (AM). In particular, a moving mesh is attached to the moving heat source while a fixed background mesh covers the rest of the computational domain. The thermal field of the moving mesh is solved in the heat source reference frame. The chosen framework to couple the solutions on both meshes

A novel approach for the solution of linear elasticity problems is introduced in this communication, which uses a hybrid chimera-type technique based on both finite element and improved element-free Galerkin methods. The proposed overset improved element-free Galerkin-finite element method (Ov-IEFG-FEM) for linear elasticity uses the finite element method (FEM) throughout the entire problem geometry

Metal-ceramic composites by their nature have thermal residual stresses at the micro-level, which can compromise the integrity of structural elements made from these materials. The evaluation of thermal residual stresses is therefore of continuing research interest both experimentally and by modeling. In this study, two functionally graded aluminum alloy matrix composites, AlSi12/Al2O3 and AlSi12/SiC

An intrusive Reduced Order Model (ROM) is developed for nonlinear porous media flow problems with transient and time-discontinuous fluid injection rates. The proposed ROM is significantly more computationally efficient than the Full Order Model (FOM). The training regime is generated using the FOM with constant injection rates during the offline stage. The trained ROM exhibits high accuracy for complex

Wave propagation in elastodynamic problems in solids often requires fine computational meshes. In this work we propose to combine stabilized finite element methods (FEM) with an artificial neural network (ANN) correction term to solve such problems on coarse meshes. Irreducible and mixed velocity–stress formulations for the linear elasticity problem in the frequency domain are first presented and discretized

A generalized finite element beam with an embedded rotation discontinuity coupled with a 3D macroelement is proposed to assess, till complete failure (no stress transfer), the vulnerability of symmetrically reinforced concrete frame structures subjected to static (monotonic, cyclic) or dynamic loading. The beam follows the Timoshenko beam theory and its sectional behavior is described in terms of generalized

To obtain the displacement field of stiffened panel structures is very important for the online monitoring of aircraft or aerospace vehicles, etc. New inverse beam-shell elements are proposed in this study for the full-field displacement reconstruction of stiffened panels via strain measured by shell parts and rib parts simultaneously. The shell and rib parts in the stiffened panel are modeled by inverse

Conjugate heat transfer (CHT) problem of flow around a fixed cylinder is examined by using a high-order method which is based on the hybridizable discontinuous Galerkin (HDG) method. The present numerical method based on HDG discretization produces a system of equations in which the energy equation of fluid is coupled with that of solid while the continuity of heat-flux at the fluid-solid interface

This study presents a multiobjective optimization framework that integrates Artificial Neural Network (ANN) and Non-dominated Sorting Genetic Algorithm-II (NSGA-II) for the optimization of rolling process parameters of tube-to-tubesheet joint (TTT-joint). During the rolling process, both beneficial contact pressure and detrimental tensile residual stress are generated within the joint. The primary

When the finite element method (FEM) is adopted for studying strain localization problems, the mesh dependence phenomenon often ensues. The occurrence of mesh dependency will reduce the reliability of FEM simulations, so it is still worth studying. Herein, a constitutive model with decent mesh stability named the multiscale Cosserat (MC) model which contains higher-order rotation variables based on

In this study, the vibration stability (i.e., static divergence) and critical velocity of fluid-conveying, ring-stiffened, truncated conical shells are investigated under various boundary conditions. The shell is characterized using Sanders’ theory, while the fluid is modeled using a velocity potential approach with the impermeability condition at the fluid-shell interface. Using linear superposition

Rubber components are widely spread in engineering due to their mechanical properties such as high strength, elongation, and dissipation characteristics. Modeling rubber behavior poses challenges because of its complex visco-elastic properties and various nonlinear effects. As high fidelity simulations become increasingly challenging, reduction techniques such as subspace projection and hyper-reduction

The engineering design of metamaterials with selected acoustic properties necessitates adequate prediction of the elastic wave propagation across various domains and specific frequency ranges. This study proposes a systematic approach centered on the finite element characterization of the three-dimensional Green’s function for a representative volume element. The inherent characteristics of broadband

Pseudo-unidirectional fiber networks are used in a variety of applications, such as woven fabrics and needling. A method for generating pseudo-unidirectional fiber networks by extruding linear portions of fibers is described here, and consists of two steps: Initially, a deliberately disorganized pseudo-unidirectional fiber network was generated geometrically from a stochastic algorithm according to

This study introduces a biomimetic ceramic composite armor system, composed of multilayered biomimetic ceramic tiles and fiber back-plates. The ballistic performance of the composite armor against T12A steel projectiles was investigated through experimental and numerical simulation studies. The experimental findings indicate that, while the biomimetic ceramic structure demonstrates weaker ballistic

The behavior of typical corner supported bare and bonded poly-film hardened concrete plates are investigated experimentally using an Instron impact testing machine and evaluated numerically using two well-known phenomenological models of concrete. Before use, the models are critically evaluated and necessary modifications are incorporated. After validation with experimental data the better of the two

This work proposes an optimisation platform, consisting of a recently proposed parametrisation and a modified gradient-based optimiser to optimise curved beams. This parametrisation technique defines a curve by a series of alternative straight and circular arcs through the points of tangency. The design variables are the coordinates and radii of the curved (transitional) sections. The relationships

A model order reduction approach combining reduced basis (RB) projection and sub-structuring by domain decomposition is developed to tackle nonlinear elasto-plasticity in parametrized coupled thermo-hydro-mechanical (THM) systems. The region-specific occurrence of plasticity in the THM process is exploited in domain decomposition to facilitate the simplified construction of localized reduced subspaces

This paper deals with the simulation of parametrized strongly-coupled multiphysics problems. The proposed method is based on previous works on multiphysics problems using the LATIN algorithm and the Proper Generalized Decomposition (PGD). Unlike conventional partitioning approaches, the LATIN-PGD solver applied to multiphysics problems builds the coupled solution by successively adding global corrections

Spark plasma sintering (SPS) is a widely used technique for sintering thermoelectric devices. In this process, the heat generated by Joule heating is primarily transferred to the die surface through radiative heat transfer, causing temperature non-uniformity within the specimen. These discrepancies in temperature distribution cause localized changes in the properties of the thermoelectric device, which

In this work, we propose the application of the eXtended Finite Element Method (XFEM) in the context of the coupling between three-dimensional and one-dimensional elliptic problems. In particular, we consider the case in which the 3D–1D coupled problem arises from the geometrical model reduction of a fully three-dimensional problem, characterized by thin tubular inclusions embedded in a much wider

In the Directed Energy Deposition (DED) process, when the mass flow of metal particles is relatively high, the thickness of the layers increases, leading to a more productive process. The higher the mass flow is, the more difficult it becomes to get a stable melt pool. The accumulation of residual heat in the previously consolidated material constitutes a thermal input affecting the balance at the

This work is the second of a two-part research project focused on modeling solid-shell elements using a stabilized two-field finite element formulation. The first part introduces a stabilization technique based on the Variational Multiscale framework, which is proven to effectively address numerical locking in infinitesimal strain problems. The primary objective of the study was to characterize the

A comprehensive model has been developed to couple CFD with the population balance equation (PBE) for a flat sheet membrane-assisted antisolvent crystallization (FS-MAAC) process. The model accurately depicts the fluid dynamics, mass transfer, heat transfer and crystal size distribution (CSD) in the FS-MAAC crystallizer. The crystallization system considered was to produce α-form crystals of glycine

This study proposed effective finite element methods for simulating the fillet welding process on T-shaped joints. The T-shaped fillet welded joints were fabricated, and the process was simulated by a Continuous Distributed heat input method (CD method) and combining shell and solid elements. This study compared the models by the Discontinuous Uniform heat input method (DU method) and the CD method

A multiscale computational framework to capture stress concentrations and localized nonlinearity in composite structures is presented. An enriched approximation space, constructed using the generalized finite element method (GFEM), is used to incorporate nonlinear, heterogeneous material behavior into coarse-scale models on the fly. Enrichment functions are constructed using the GFEM with global–local

This work studies the solid-shell finite element approach to approximate thin structures using a stabilized mixed displacement–stress formulation based on the Variational Multiscale framework. The work is divided in two parts. In Part I, the numerical locking effects inherent to the solid-shell approach are characterized using a variety of benchmark problems in the infinitesimal strain approximation

Polymeric materials find extensive applications across various engineering sectors. Among these, a particularly critical application for these materials is in the field of roller coasters. The wheels are typically made with an aluminum hub and a dense polyurethane coating, which, being in contact with the track, endures dynamic loads at high speeds. Due to the viscoelastic behavior typical of polymeric